Absorbent product with improved fit

ABSTRACT

An absorbent product, such as a sanitary towel, includes a stiffening element ( 6 ) which is intended to contribute to the three-dimensional shape of the product during its use. The stiffening element ( 6 ) is in a plane state before use of the product and has a stiffness in the dry state of in the order of 1-15 N measured according to ASTM D 4032-82. The stiffening element has a width at the transition between the crotch portion ( 3 ) and the front portion ( 1 ) on the sanitary towel which is adapted to the distance between the muscle tendons of the wearer on both sides of the crotch of the wearer in the groin of the latter and which is of the order of 15-45 mm. The product has different stiffness along a center line extending in the longitudinal direction thereof, as a result of which the product is predestined to curve in predetermined places along the center line when the product is fitted on the wearer.

This application claims priority under 35 U.S.C. §119 to U.S.Provisional Application No. 60/284,888 entitled ABSORBENT ARTICLE WITHIMPROVED FIT filed and filed on Apr. 20, 2001, the entire content ofwhich is hereby incorporated by reference.

TECHNICAL FIELD

The present invention relates to an absorbent product, such as asanitary towel, a panty liner, an incontinence pad, a nappy or the like,which product has a longitudinal direction and a transverse direction, afront portion, a rear portion, a crotch portion located between the rearportion and the front portion, an absorbent element and a liquidtightlayer and also a stiffening element which is intended to contribute tothe three-dimensional shape of the product during its use.

BACKGROUND ART

A great many requirements are made of absorbent products, such as asanitary towel, an incontinence pad, a nappy or the like, which are noteasy to satisfy simultaneously. A fundamental requirement is that theproduct, for example a sanitary towel, will be capable of catching andabsorbing bodily fluid discharged from the wearer. Conventional sanitarytowels in sizes intended for heavy flows of menstrual fluid have been ofthick and relatively wide design. Sanitary towels of this type aredescribed in, for example, U.S. Pat. No. 3,294,091. Thick and relativelywide sanitary towels of this type theoretically have great absorptioncapacity but in practice, when the sanitary towel is subjected tocompression forces when squeezed together between the thighs of thewearer, much of the take-up capacity and absorption capacity is lost.The sanitary towel is squeezed together into an arbitrary rope-likeshape which frequently does not offer a sufficiently large receivingsurface for the menstrual fluid discharged, and leakage occurs in thecase of heavy flows of menstrual fluid. The sanitary towel can also bepressed together between the thighs of the wearer in such a manner thatthe side edges of the sanitary towel and the liquidtight layer arefolded in over the liquid-permeable surface and in this way reduce thesize of the liquid-receiving surface available.

Sanitary towels are intended to be positioned inside a pair of briefs,the design of which may vary. In this connection, sanitary towels can bepositioned incorrectly inside the briefs. There is therefore a risk ofthe sanitary towel being, by mistake, positioned too far forward or toofar back or displaced slightly in the lateral direction and therefore ofthe absorption capacity and receiving surface of the whole sanitarytowel not being optimally utilized.

Conventional sanitary towels are generally retained in the briefs of thewearer by means of pressure-sensitive adhesive or friction coatings. Thesanitary towel is fitted by being put in position in the briefs, afterwhich the latter are pulled up into position. When fitting the productinside the briefs, however, it is difficult to achieve a positioningwhich is optimum in relation to the body of the wearer. Use is usuallymade of the crotch portion of the briefs in order to determine where thesanitary towel will be positioned. As sanitary towels are manufacturedin a great many sizes and models, the position and design of the crotchportion provide a particularly unreliable indication of where in thebriefs a sanitary towel is to be positioned, and the functioning of thesanitary towel during use is consequently not always as desired.

Another cause of leakage occurring past sanitary towels attached insidethe briefs of the wearer is that the sanitary towel moves together withthe briefs instead of following the body movements of the wearer. Thismeans that even a sanitary towel which was from the outset positionedcorrectly in the briefs in relation to the body can be pulled out ofthis position by the briefs.

In order to attempt to reduce leakage arising as a result of thesanitary towel being pressed together between the legs of the wearer, ithas become usual to provide the sanitary towels with special attachmentflaps. It is known from, for example, SE 455 688, U.S. Pat. No.4,285,343, EP 0 130 848, EP 0 134 086 and U.S. Pat. No. 4,608,047 toprovide sanitary towels with flexible side flaps or wings projectingfrom the longitudinal side edges. These are intended to be folded aroundthe edge portions of the briefs of the wearer when the sanitary towel isput on and attached to the outside of the briefs. The side flaps per seconstitute protection against side edge leakage and soiling of thebriefs. Moreover, deformation of the absorption body of the sanitarytowel is counteracted by virtue of the fact that the sanitary towel isanchored at the leg edges of the briefs and is held extended betweenthese during use.

However, a considerable disadvantage of providing absorbent productswith such attachment flaps is that many wearers find it embarrassingthat the attachment flaps are visible on the outside of the briefs. Thisalso means that absorbent products with such attachment flaps cannot beused when, for example, the wearer is wearing a swimsuit.

Another disadvantage of the attachment flaps is that they are relativelydifficult to handle and require many manual operations in order to befitted correctly around the leg edges of the briefs. Furthermore,especially in the case of attachment flaps which extend quite a long wayalong the side edges of a sanitary towel, it can be virtually impossibleto fold the attachment flaps around the curved leg edges of the briefswithout chafing and unattractive creases in the attachment flapsoccurring.

A further problem of sanitary towels with attachment flaps is that thefunctioning of the attachment flaps or wings depends on the design ofthe briefs. It goes without saying that a sanitary towel with attachmentflaps interacts differently with briefs with a wide crotch compared withbriefs with a very narrow crotch.

Attachment flaps or wings on sanitary towels protect the leg edges ofthe briefs from soiling but, as emerged above, are far from being anentirely satisfactory solution.

In order to improve leakproofness, EP 0 067 465 has proposedmanufacturing a two-part sanitary towel in which the two parts areinterconnected only at their end portions. The lower part is fastened inthe briefs of the wearer, and the upper part makes contact with the bodyof the wearer. The idea is that the parts will be able to move slightlyin relation to one another during use. The mobility between the partsis, however, very limited, and the known sanitary towel is stilldependent on the movements of the briefs. Furthermore, there is noguarantee that the upper part will be held in contact with the body ofthe wearer during use.

PCT/SE96/01061 describes another two-part absorbent product in which thetwo parts are movable in relation to one another. This known productalso has limited mobility between the parts and is to a certain extentdependent on the movements of the briefs.

One way of attempting to reduce the risk of edge leakage caused bydeformation of the sanitary towel during use is to provide the sanitarytowel with a preshaped raised portion, what is known as a hump, which isintended to make contact with the genitals of the wearer during use ofthe sanitary towel. Discharged bodily fluid can in this way be caught assoon as it leaves the body of the wearer and immediately be caught assoon as it leaves the body of the wearer and be absorbed immediatelyinto the product instead of running out over the surface of the latter.A raised portion also makes it easier for the wearer to position theproduct correctly in relation to the body. French patent publicationFR-A-2 653 328 describes a sanitary towel with a hump in the form of acentral, longitudinal, cylindrical raised portion.

A common way of creating a raised portion has been quite simply to buildit up by arranging a greater quantity of absorption material within thearea of the raised portion. As the absorption material used is in mostcases what is known as cellulose fluff pulp, however, such a raisedportion collapses and loses its shape when it is wetted. In order toproduce a raised portion which is sufficiently large in the wet state aswell, a raised portion consisting of cellulose fluff pulp must compriseso much absorption material that it is altogether too high, hard anduncomfortable to wear in the dry state.

It is also known to produce an article with a raised portion facing thewearer by positioning a shaping element on top of the absorbent core.The disadvantage is that this interferes with the liquid transport downto the absorbent, liquid-retaining absorption core and that leakage canoccur because the shaping element does not have sufficient admissioncapacity or temporary retention capacity. The use of, for example, afoamed material in the raised portion has been proposed. However, it hasproved difficult to produce a foamed structure with sufficiently openpores for good liquid admission into the latter at the same time as thematerial is to have such great retention capacity that liquid is notpressed out in the event of loading originating from the wearer, forexample when the latter sits down.

Another example of a raised portion is described in Swedish patent 507798. Such a raised portion has a predictable shape, both before andduring use, and also keeps its shape irrespective of the movements ofthe wearer and of the wetting to which it is subjected. The raisedportion is anatomically designed, which means that it is relativelynarrow in order to project in slightly between the labia of the wearerduring use without causing discomfort for the wearer.

Although such a raised portion functions well for its purpose, it hasbeen found that when the raised portion is exposed to large quantitiesof bodily fluid over a relatively short period of time, there is a riskthat some of the liquid will run on the outside of the raised portionand flow out past the side edges of the absorbent product. Such leakagecan occur, for example, when the wearer of a sanitary towel has beensitting or lying down for a relatively long period of time and thensuddenly rises. This is because, when the wearer is sitting or lyingdown, a relatively large quantity of menstrual fluid accumulates in thevagina of the wearer. In the event of a sudden change in body position,the entire quantity of accumulated liquid may be discharged at once. Anarrow raised portion of the type described in SE 507 798 does not thenhave a sufficiently large surface to be capable of receiving andabsorbing the entire quantity of liquid in one go, for which reason suchsudden liquid flows often result in leakage.

EP 0 335 252 and EP 0 335 253 have proposed providing an absorbentproduct with a deformation element. The deformation element is acted onby the transverse compressive forces between the thighs of a wearer. Thepurpose of the deformation element is to cause a portion of the productto bulge in the direction of the body of the wearer during use. It isimpossible, however, to control or predict entirely the shape theproduct will adopt for each individual wearer. Moreover, it is notpossible to ensure contact between the body of the wearer and thesurface of the product, because the degree of bulging is determinedentirely by how much the product is compressed in the transversedirection.

U.S. Pat. No. 4,804,380 describes an absorbent product which has apermanent three-dimensional shape. The product has one end portion offlat or concave shape and one end portion provided with a raisedportion. The flat or concave end portion is intended to be positioned infront of the mons Veneris of the wearer, and the end portion comprisingthe raised portion is intended to fit between the buttocks of thewearer. The three-dimensional design of the product is brought about byfolding a fairly stiff absorption body. In order to make the raisedportion permanent, the rear side of the product in the end portion whichis to have the raised portion is provided with a glued surface. When theraised portion has been formed, it is maintained by means of the glue.

There are absorbent products on the market which have a permanent,three-dimensional, boat-like shape and in which the outer shell consistsof a moulded polymer foam.

A considerable disadvantage of permanent three-dimensional products isthat it is difficult to pack a stiff three-dimensional product. Suchproducts require a great deal of space for transport and sale, and itcan be embarrassing for a wearer to carry around a sanitary towel or anincontinence pad which it is impossible to fold and therefore cannot beconcealed in the hand or in the worst case will not even fit in ahandbag.

EP 155 515 describes how an absorbent product, such as a sanitary towel,is imparted a bowl-shaped appearance by virtue of elastic being appliedin a pretensioned state at the longitudinal side edges of the product.The use of elastic complicates manufacture, and there is a risk of theintended elastic effect being lost in connection with packing of theproduct or when the latter is stored in a folded packing state.

It is previously known to design plane absorbent products which adopt athree-dimensional, essentially bowl-like shape when applied. An exampleof this is described in U.S. Pat. No. 4,655,759. This discloses anelongate sanitary towel which consists of a layer of absorbent material,a flexible liquidtight outer layer and a liquid-permeable inner layer.The sanitary towel is provided with a pair of channels formed bystamping, the channels being located on both sides of a longitudinalcentre axis and extending along a curved path over the absorptionmaterial layer. The two paths together form an hourglass-like shapepositioned centrally over the towel. Before use, the sanitary towels areessentially plane but, when they are applied to the wearer, they arefolded into a bowl-like shape, that is to say with liquid-stoppingupright borders outside the channels. A disadvantage of this bowl-likeconstruction is that the borders hold the central portion of thesanitary towel at a distance from the genitals of the wearer, and liquiddischarged from the wearer does not flow directly into the absorbentproduct but can run on the surface, the risk then being obvious thatliquid may find an undesirable transport path in the form of a smallcrease or the like and run straight out of the product in the lateral orlongitudinal direction. Stamped channels in an absorption body also havethe disadvantage that the liquid spread in the absorption layer isdisrupted and that absorption material outside the channels is notutilized, which increases the risk of local oversaturation and attendantleakage from those parts of the absorption layer which are used.

Previously known sanitary towels and the various problems associatedwith them have in the main been discussed above. However, what has beensaid above also applies to incontinence pads. Nappies for children andadults also belong to the same problem area as far as fit in the crotchand take-up of liquid in an absorption body are concerned.

As emerged above, great efforts have been made over many years in orderto attempt to solve all the problems associated with absorbent products,such as sanitary towels. Although great improvements have been made, allthe previously known solutions are associated with some disadvantages.

DISCLOSURE OF INVENTION

By means of the present invention, an improved absorbent product of thetype mentioned in the introduction has been produced. The productaccording to the invention is characterized mainly in that thestiffening element is in a plane state before use of the product, inthat the stiffening element extends in the longitudinal direction of theproduct over the crotch portion and at least some way in over the frontportion, in that the stiffening element has a stiffness in the dry stateof in the order of 1-15 N measured according to ASTM D 4032-82, in thatthe stiffening element has a width at the transition between the crotchportion and the front portion which is adapted to the distance betweenthe muscle tendons of the wearer on both sides of the crotch of thewearer in the groin of the latter and which is of the order of 15-45 mm,and in that the product has different stiffness along a centre lineextending in the longitudinal direction thereof, as a result of whichthe product is predestined to curve in predetermined places along saidcentre line when the product is fitted on the wearer.

By adapting the stiffness of the product along its centre line, theproduct can be made to curve in predetermined places along said centreline, that is to say so that folds are formed in the transversedirection of the product in said places. When the product is fitted inposition, it is natural for the wearer to position the product with saidtransition in the correct place on the body, that is to say at saidmuscle tendons. The product will then automatically curve in saidpredetermined places, which are of course selected so that optimumadaptation of the product to the human body is achieved.

An absorbent product according to the invention has a number ofadvantages. It is plane before use, and there are therefore no problemsassociated with packing, storing and transporting said product.

The crotch portion suitably has a length of 70-120 mm. This length isselected in order to fit the body of the wearer. Most women have a planecrotch portion of in the order of 80-100 mm. A length of 70-120 mm alsofits men and children.

According to a suitable embodiment, the invention is characterized inthat the side edges of the stiffening element in the front portion ofthe product diverge in the direction from the crotch portion at leastsome way in over the front portion, and in that the side edges of thestiffening element, in the direction from the crotch area, form an acuteangle with a line in the longitudinal direction of the product.

An absorbent product according to this embodiment of the inventionautomatically adopts a three-dimensional bowl-like shape in an area inthe front portion next to the crotch portion when the product is, at itstransition between the front portion and the crotch portion, fixed inbetween said muscle tendons. It is known that the distance between saidmuscle tendons is very similar for all people. Fatness of course has aneffect on the width between the thighs, but the width between the musclegroups is the same, and it is these which may cause a product to feel asif it chafes. The fat tissue lies on the outside of the muscles but doesnot contribute to any sensation of discomfort. The distance between saidmuscle tendons is the same irrespective of whether the wearer is slim,of normal weight or overweight. It has been found that what determineswhether a wearer experiences discomfort in the form of pressure orchafing against the insides of the thighs is whether the absorbentproduct has a width during use which in the critical area considerablyexceeds the distance between the muscle tendons in the groin portion.This distance has been found to be roughly 25-45 mm. It has been foundthat a product with a width which exceeds 40 mm in the critical areaduring use feels uncomfortable to wear to the majority of wearers. Onthe other hand, it is rarely experienced as being unpleasant if anabsorbent product pushes down or aside fat tissue which may be presentin the crotch area of the wearer.

Surprisingly, it has been found that this distance between said muscletendons does not change throughout the lifetime of a person. Smallinfants therefore have a corresponding critical distance, which,according to the present invention, can be utilized for producingnappies with an improved fit. The same of course applies for nappies foradults. It is to be pointed out that said critical distance between themuscle tendons applies for men also, who have the same distance betweensaid muscle tendons.

A product designed according to the invention is adapted to the anatomyof the wearer. The special geometry around the transition between thecrotch portion and the front portion results in a product being anchoredfirmly in the groins of the wearer during use, and in this way theproduct is prevented from moving backwards between the legs of thewearer. This is otherwise a common problem in conventional productsbecause the leg movements of the wearer often shift the productbackwards.

According to an especially preferred embodiment, the invention ischaracterized in that the stiffening element is absorbent and at thesame time constitutes the absorbent element, and in that it swellsduring absorption while retaining its geometry in the transversedirection of the product.

It is possible of course to have a separate stiffening element behindthe absorption element, seen from the side facing the wearer. However,in terms of production, it is simpler if a separate stiffening elementcan be eliminated. It is of course preferable from an environmentalpoint of view also.

The width of the stiffening element at the transition between the crotchportion and the front portion is suitably of the order of 20-35 mm. Ithas been found that a width at said transition of 30-32 mm fits well forin the order of 80% of all wearers. According to a particularly suitableembodiment, the invention is characterized in that said width of thestiffening element at the transition between the crotch portion and thefront portion is of the order of 25-30 mm.

According to a preferred embodiment, the invention is characterized inthat the stiffening element consists of a dry-formed fibre mat with adensity between 0.15 and 0.75 g/cm³ and a weight per unit area of in theorder of 100-400 g/m².

In this context, the term density means the density of the fibrousmaterial, that is to say any highly absorbent particles included in thefibrous material are not to be taken into account.

Said dry-formed fibre mat is described in U.S. Pat. No. 5,730,737. Thefibre mat produced is very stiff after forming and compression. Thefibre mat can be used as it is or mechanically softened to the desiredstiffness.

According to a suitable embodiment, the product according to theinvention is characterized in that the side edges of the stiffeningelement, which diverge at least some way from the crotch portion in overthe front portion of the product, are arranged so as to form an anglebetween a line in the longitudinal direction of the product and each ofsaid side edges of in the order of 35-55°, preferably in the order of45°. With this geometry in and around the transition between the crotchportion and the front portion, effective anchoring is obtained withoutthe wearer experiencing any discomfort in the form of chafing or thelike.

According to a preferred embodiment, the product according to theinvention is characterized in that the stiffening element also extendssome way in over the rear portion of the product, and in that the sideedges of the stiffening element, in the direction from the crotchportion, diverge at least some way from the crotch portion in over therear portion of the product. As mentioned above, the crotch portion ofcourse has a length of 70-120 mm. This length corresponds to the lengthof a plane portion in the crotch portion of a woman. The stiffeningelement according to the last embodiment is therefore anchored both atthe rear and at the front at the transition between the crotch portionand the rear portion and, respectively, at the transition between thecrotch portion and the front portion, as a result of which a productwhich is very stable, well fixed and at the same time comfortable duringuse is obtained.

Further advantageous embodiments of the product according to theinvention emerge from the subsequent patent claims.

BRIEF DESCRIPTION OF DRAWINGS

The invention will be described in greater detail below with referenceto illustrative embodiments which are shown in the accompanyingdrawings, in which:

FIG. 1 shows a plan view of an absorbent product according to a firstembodiment;

FIG. 2 shows a section along the line II—II in FIG. 1 but in a curvedutilization state;

FIG. 3 shows an embodiment, slightly modified in relation to theembodiment according to FIG. 1, of a product according to the inventionin a plan view;

FIG. 4 shows a section along the line IV—IV in FIG. 3;

FIG. 5 shows a plan view of a third embodiment of the product accordingto the invention;

FIG. 6 shows a plan view of a fourth embodiment of the product accordingto the invention seen towards that surface of the product which receivesbodily fluids;

FIG. 7 shows a plan view of the product according to FIG. 6 from theopposite side;

FIG. 8 shows a section along the line VIII—VIII in FIG. 6 but in acurved utilization state;

FIG. 9 shows the product according to the fourth embodiment, also shownin FIGS. 6-8, in perspective and in a utilization state;

FIG. 10 shows a plan view of a fifth embodiment, slightly simplified inrelation to the embodiment according to FIGS. 6-9, and

FIG. 11 shows a plan view of an absorbent product according to theinvention in the form of a nappy.

MODE(S) FOR CARRYING OUT THE INVENTION

FIGS. 1 and 2 show a product according to the invention in the form of asanitary towel or incontinence pad. The product is elongate with alongitudinal direction and a transverse direction. The product has afront portion 1, a rear portion 2 and a crotch portion 3 located betweensaid portions. The product shown in FIGS. 1 and 2 comprises aliquid-permeable inner layer 4 which is intended to face the wearerduring use of the product. The inner layer, which makes contact directlywith the skin of the wearer, is suitably made from a soft, textile-likematerial. Examples of suitable liquid-permeable materials are varioustypes of what are known as non-woven fabrics. Other examples of suitablematerials are perforated plastic films. Net and knitted or woventextiles and combinations and laminates of said materials can also beused as the inner layer. Examples of inner layers for sanitary towelsare laminates of different non-wovens and laminates of non-wovens andperforated plastic films. The liquid-permeable layer can also beintegrated with underlying drainage or absorption layers, for example afoam plastic with open pores and with a density gradient in the depthdirection can serve as a surface layer and as a drainage layer and/orabsorption layer.

The absorbent product also has a liquidtight outer layer 5. This usuallyconsists of a thin plastic layer, made of polyethylene for example. Itis also possible to use a liquid-permeable material which has beentreated with hydrophobing agent in order to make it liquidtight. Inparticular if the absorbent product is relatively large, it may besuitable for the outer layer to be vapour-permeable in addition to beingliquidtight. Such layers can consist of hydrophobed non-woven fabric orof porous plastic films.

The absorbent product includes an absorbent element 6 of keyhole-likeshape, and a liquid-permeable insulating layer 7 which likewise has akeyhole-like shape but with a greater extent in both the longitudinaldirection and the transverse direction than the absorbent element 6. Theouter layer 5 and the inner layer 4 extend with edge portions outsidethe insulating layer around the latter and are interconnected alongthese edge portions to form a cover around the absorbent element 6 andthe insulating layer 7. In the region of the crotch portion 3, the coverformed by the inner and outer layers extends outwards in the lateraldirection to form flexible side flaps 8, 9, what are known as wings,which are intended to be arranged around the crotch portion on thebriefs of the wearer in order to protect the edge portions of the briefsfrom soiling. The wings 8, 9 are suitably provided with adhesivecoating, which is indicated in FIG. 1 by reference numbers 10, 11, onthe outer layer 5, by means of which the wings can be attached aroundthe legs of the briefs. As can be seen from FIG. 2, the insulating layer7 is located directly inside the inner layer 4 and is principallyintended for rapidly admitting discharged bodily fluid into theunderlying absorbent element 6 and forming a liquid-insulating layer soas to reduce what is known as back-wetting from the absorbent element 6to the inner layer 4 making contact directly with the wearer.

The insulating layer can consist of, for example, an airlaid fibrousmaterial of low density bonded together with bonding agent orthermofibre, which is marketed under the designation LDA (low densityairlaid). The absorbent element 6 is, seen from the liquid-permeableinner layer 4, arranged under the insulating layer 7. In the productaccording to the invention, this element is designed to take up andretain essentially all the bodily fluid discharged. The absorbentelement 6 has smaller capillaries than the insulating layer 7 locatedabove and therefore draws liquid from the insulating layer and preventsback-wetting by liquid from the absorbent element to the insulatingelement and to the inner layer 4 which remains essentially dry duringuse of the product. Only when the absorbent element is saturated withliquid can transport take place from the absorbent element to theinsulating layer.

In the illustrative embodiment shown, the absorbent element 6 is alsointended to serve as a stiffening element and is for this purposedesigned so as to be very stiff in order as far as possible to avoid theabsorbent product being compressed in an uncontrolled manner in theevent of squeezing forces in the lateral direction generated by thethighs of the wearer in the crotch area. The absorbent stiffeningelement has a size, shape and stiffness which result in the product,throughout its time of use, retaining a predetermined shape and moreoverbeing retained in the intended position on the wearer. As can be seenfrom FIG. 1, the absorbent stiffening element 6 extends over the frontportion, the entire crotch portion 3 and a considerable part of the rearportion 2.

At the transition 12 between the crotch portion 3 and the front portion1, the stiffening element 6 has a width M which is adapted to thedistance between two particular muscle tendons on both sides of thecrotch of the wearer directly in front of the groins. These muscletendons form part of the muscle group which originates on the inside ofthe pelvic diaphragm and has its attachment along the thigh. This musclegroup consists of the adductor brevis, adductor longus, gracilis andadductor magnus muscles. As mentioned above, it is known that thisdistance between said muscle tendons is very similar for all people.This dimension is in the order of 25-45 mm. Research has shown that 80%of all women have a dimension of 30-32 mm between said muscle tendons.When said width M essentially corresponds to the distance between saidmuscle tendons on the wearer, the product will during use be anchoredfirmly with the transition portion between the muscle tendons and beretained in this position. The two side edges of the front portiondiverge in the forward direction on the product from the transition 12.In this way, the product is prevented from moving backwards between thelegs of the wearer. This is a common problem in conventional sanitarytowels because the leg movements of the wearer often shift the sanitarytowel backwards.

In FIG. 1, an angle between a line in the longitudinal direction of theproduct and each of said side edges has been designated by α. In thecase of a large angle α, for example close to 90°, the edges of thefront portion may chafe against the groins and legs of the wearer and inthis way cause discomfort for the wearer. The smaller the angle α, thegreater the risk that the product will slide backwards in between thelegs of the wearer. In the case of an angle of less than 30°, this riskis unacceptably high. An angle of 35-45° provides the best balancebetween secure positioning and comfort. An angle of 45° has been foundto be especially favourable.

An absorbent product, such as a sanitary towel, according to theinvention is designed with a crotch length adapted to the anatomy of thewearer. In a sanitary towel according to the invention, use has beenmade of the fact that the great majority of women have a crotch lengthof in the order of 80-100 mm. The stiffening element 6 has thereforebeen designed with a corresponding crotch length G of in the order of70-120 mm, that is to say the distance from the transition area 20 tothe start of the rear portion. Along the crotch, where the body shape ofthe wearer is essentially plane, the sanitary towel according to theinvention is designed so as in the dry state to be relatively stiff inthe lateral direction, that is to say it is sufficiently stiff not to bedeformed in the lateral direction and form creases. As the stiffeningelement 6 in the embodiment described here also constitutes the majorpart of the absorption capacity of the sanitary towel, it is essentialto be capable of utilizing available space between the legs of thewearer in the crotch. The width of the sanitary towel in the crotch areais, with regard to the stiffening element, limited at the front by saiddistance between said muscle tendons directly in front of the groins ofthe wearer. In the backward direction from said transition area to theend of the crotch portion, the width of the stiffening element 6 andthus the absorbent element can increase continuously to in the order of1.5 times the width at the transition area 12 between the crotch portionand the front portion without any risk of the stiffening element chafingthe wearer in the crotch.

The abovementioned geometrical design of the area in and around thetransition 12, that is to say the size of the angle α and the width M,and also the selected crotch length G on the stiffening element for theproduct according to the invention, affords a very good anatomicaladaptation of the stiffening element, which gives the product a good fitand stability of the product in the fitted position on the wearer. Thisis of particularly great importance for the functioning of the product,not least because the wetting point can, on account of the body positionof the genitals of the wearer in the longitudinal direction of thecrotch area, vary by as much as in the order of 20 mm for differentwearers. As the available space around the wetting point is very limitedin width and length, optimum positioning and anchoring in this positionof the stiffening absorbent element is necessary. This is achieved bymeans of said distances M and L selected and said angle α selected.

The anchoring effect is achieved at said muscle tendons even when thewidth M on the product is less than the distance between said muscletendons directly in front of the groins. The two edge portions of thefront portion diverge in the forward direction, and the product canslide backwards slightly until the edge portions are anchored firmlybetween said muscle tendons. The distance M on the product is suitablyof the order of 15-35 mm and preferably 25-30 mm. The latter distancefits most wearers. If the distance exceeds roughly 35 mm, the productmay feel uncomfortable to some wearers. A distance in excess of 45 mm isunsuitable because such products cause discomfort in the form of chafingfor most wearers.

The stiffening element 6 and therefore the absorption element alsoextend some way in over the rear portion 2 of the product. In the rearportion, the stiffening element has a cutout 13 extending from the endedge of the element in the direction of the crotch portion, as a resultof which the product can fold along a longitudinal line in the cutoutand the parts, the legs 14 and 15, which are located on both sides ofthe cutout are more flexible than the wider crotch portion and can bemade vertically movable in relation to one another by selecting thewidth of the cutout accordingly. This cutout 13 is very important forthe adaptation and flexibility of the product in relation to the body.The fold in the cutout can penetrate the cleft between the buttocks ofthe wearer and in this way provides very good protection against leakagevia the cleft between the buttocks, which type of leakage usually occursduring the use of conventional products when the wearer is lying on herback. The cutout 13 also makes it possible for said legs 14, 15 on thestiffening element to be displaced vertically in relation to one anotherduring different body movements, for example when the wearer is walking.

In the illustrative embodiment shown in FIG. 1, the cutout 13 iswedge-shaped and located symmetrically in relation to the longitudinalsymmetry line L of the product and also forms an angle β of in the orderof 20°. This angle can vary within wide limits but of course depends onthe design of the rear portion 2. In the case of a considerably widerdesign of the rear portion, such as in the design according to FIG. 5,said angle β can vary between 10° and 120°, preferably between 15° and40°.

The stiffening element 6 also serves as the main absorption element ofthe product and has very great liquid-spreading capacity for rapidspreading of bodily fluid received from the wearer in the narrow crotcharea directly in front of the genitals of the wearer over the absorbentportions of the whole product, that is to say over the entire stiffeningand at the same time liquid-absorbing element 6. This stiffeningabsorbent element is designed so as to swell in the depth directionduring absorption and on the whole retain its geometry in the transversedirection of the product, which results in the stiffening elementretaining its fit and secure positioning in relation to the body of thewearer throughout use of the product. The absorbent stiffening element 6has great swelling capacity in the depth direction and attendant greatabsorption capacity.

According to a suitable embodiment, the stiffening absorbent element 6consists of a dry-formed fibre mat with a density between 0.15 and 0.75g/cm³ and a weight per unit area of in the order of 100-400 g/m². Adry-formed fibre mat is described in U.S. Pat. No. 5,730,737. The fibremat produced is very stiff after forming and compression. The fibre matcan be used as it is or mechanically softened to the desired stiffness.

The selection of compression pattern also makes it possible to vary theextensibility of the fibre mat. The dry-formed fibre mat can be impartedthe desired reduced stiffness and the desired extensibility by virtue ofthe degree of compression selected and the compression pattern selected.

Furthermore, it is possible to pattern-compress only specific zones forthe purpose of imparting to only these zones an extensibility andstiffness which are different from the rest of the stiffening absorptionelement. In the same way, the stiffening absorption element can becompressed over its entire extent but with different patterns indifferent zones. By means of the presence of a stiffening absorptionelement which can in a simple manner, by virtue of the patterncompression selected, be imparted the desired stiffness and the desiredextension in different zones, and in which the stiffness and extensionproperties can be selected essentially freely in these zones, thepresent invention has brought about a new and previously unknown way ofcontrolling and guiding the shaping of an absorbent product intended fortaking up bodily fluids.

As mentioned above, the stiffening absorbent element 6 has greatswelling capacity in the depth direction, which, when a dry-formed fibremat as above is used, has been achieved by great compression of thefibre mat in conjunction with its production. In the dry state, thefibre mat is hard-compressed and stiff, which affords the shaped andanatomically adapted absorption element very good stability in thefitted position on the wearer and very great spreading capacity, as aresult of which the total absorption capacity of the absorption elementcan be optimally utilized and leakage caused by local oversaturation canto a great extent be eliminated. During absorption of liquid, theabsorption body swells mainly in the depth direction but the absorptionelement does of course swell slightly in other directions as well. Whenthe anatomically adapted stiffening absorption element swells, furtherimproved anatomical adaptation is in fact achieved, which contributes tothe stability and flexibility of the product in relation to the bodyshape of the wearer when the stiffness of the absorption elementdecreases during absorption and attendant swelling.

So as to function in the desired manner, the stiffening element has astiffness of in the order of 1-15 N measured according to ASTM D4032-82. This “Circular Bend Procedure” is described in detail in U.S.Pat. No. 4,950,264.

The stiffening absorbent element can also consist of a laminate of anumber of non-woven fabric layers or tissue layers which are mutuallyfixed for increased stiffness and which have highly absorbent particlesbetween the individual layers. The individual layers can be fixed to oneanother by a bonding agent, such as adhesive or melt fibres. The highlyabsorbent particles can also contribute to bonding. The stiffness iscontrolled by means of the selection of the number of layers andquantity of bonding agent included and the selection of highly absorbentmaterial and how the adhesive capacity thereof is utilized.

A stiffening absorbent element of this type can also be imparteddifferent stiffness and different extensibility in different zones ofthe extent of the element. These properties can in this case as well becontrolled by means of the compression pattern. This compression can becombined with the supply of heat, which supply can vary in differentzones. Furthermore, bonding agent can be applied in different patternsto control the shaping of the stiffening absorption element during use.A varying supply of moisture in different areas is another parameter forcontrolling the shaping of the product during use.

Another example of the construction of a unit serving as both absorptionelement and stiffening element is a number of layers of LDA, that is tosay layers of the same type as in the draining and insulating layer 7.However, the layers of LDA in the stiffening absorption element arebonded much more firmly both within and between the individual layers.This bonding is suitably brought about by using both melt fibres andlatex, what is known as the multibond technique. In this design as well,stiffness and extensibility can be controlled by means of the selectionof compression pattern and by variation of the heat supply in differentzones.

Pattern compression can be used in all the material examples describedabove, and it is then possible to achieve, for example, hinge effectsalong compression lines or compression zones.

Pattern formation can take place in conjunction with compression of thestiffening absorption element. Alternatively, pattern compression cantake place in a separate step after smooth compression. Use can be madeof, for example, a web of a smooth-compressed material made in one ofthe ways described above as the starting material for the stiffeningabsorption element, which is pattern-compressed in the desired mannerand depending on the type and size of product to be manufactured. Afterpattern-compression, individual products are cut out.Pattern-compression and cutting-out of separate stiffening absorptionelements can take place in a single step in a combined cutting andpattern-compression unit.

As described above, the stiffening element can also constitute the mainabsorption element of the product. This is particularly suitable fromthe point of view of production because there are fewer elements tohandle than if, for example, the stiffening element and the absorptionelement constitute separate elements.

The invention also comprises designs in which the stiffening element isseparate from the main absorption element of the product. The stiffeningelement can then be absorbent or non-absorbent. The main purpose is toconstitute a stiffening shaping element.

In addition to the interpretation of the term stiffening element asconstituting a completely separate element or constituting both the mainabsorption element and the stiffening element of the product, the termcan also embrace the interpretation that all the material plies, bondingagents etc. included in the product in the area of the desiredstiffening together form the desired stiffening element. For example, aunit serving as a stiffening element and at the same time as anabsorption element, with the M and G dimensions indicated above and withthe geometry described above but with stiffness which is per seinadequate, is included in the invention if the necessary stiffness isobtained by being bonded together with other material plies in the areaof the stiffening element.

The embodiment shown in FIG. 3 differs from the embodiment shown inFIGS. 1 and 2 only in that an elastic means 16 is arranged in apretensioned state in the longitudinal direction of the product andcentrally along the rear portion 2 of the product. The same referencenumbers have been used in FIGS. 3 and 4 as in the embodiment accordingto FIGS. 1 and 2.

The elastic means 16 is arranged centrally in the cutout and extends inthe rear portion slightly beyond the ends of the legs 14 and 15 and inthe other direction some way in over the crotch portion. The elasticmeans is arranged on the inside or on the outside of the liquidtightouter layer and is connected to the latter and/or other layers formingpart of the product. The extent of the elastic means is not critical butcan vary somewhat in relation to the illustrative embodiment shown inFIG. 3. The purpose of the elastic means 16 is, during use of theproduct, to draw adjacent material portions together and curve theproduct in the upward direction towards the body of the wearer forbetter contact with the body. The purpose is also to initiate and formthe fold 17 which, during use of the product, is intended to penetrate alittle way into the cleft between the buttocks of the wearer and preventleakage of bodily fluid backwards along the cleft between the buttocks,which leakage can otherwise occur when the wearer is lying on her back.

In the embodiment shown in FIG. 5, the components which correspond tosimilar parts in the embodiments according to FIGS. 1-4 have beenprovided with the same reference numbers. The product in the embodimentaccording to FIG. 5 is provided with a considerably wider rear portion2. The product also differs from the embodiments described above in thatthere are no wings for attachment around the crotch portion of thebriefs of the wearer.

The stiffening element 6 extends with its leg portions 14, 15 in overthe rear portion 2. The outer side edges 18, 19 on the legs 14, 15 ofthe stiffening element 6 diverge from the crotch portion in over therear portion. In a rear transition area 20 between the crotch portion 3and the rear portion 2, said outer edge sides 18, 19 abruptly changedirection in relation to the edge sides 22, 23 on the stiffening elementin the crotch portion of the product.

The purpose of the edge sides 18, 19 of the stiffening element divergingin the backward direction on the rear portion 2 is that the product, inaddition to being anchored firmly at the transition 12 between the frontportion and the crotch portion, will also be anchored at the rear in thetransition area between the crotch portion 3 and the rear portion 2, asa result of which the product is very stable and well fixed on thewearer during use at the same time as it feels comfortable for thewearer by virtue of its anatomical adaptation in terms of shape, sizeand geometry. In the drawing, an angle between the longitudinaldirection of the product and each outer edge side 18, 19 has beendesignated γ. For a good anchoring function, this angle should not beless than roughly 30°. Furthermore, so as not to feel uncomfortable, theangle should not exceed roughly 60°.

The distance G between the transition areas 12 and 20 is adapted to thecrotch length of a wearer and, as mentioned above in connection with theembodiments according to FIGS. 1-4, this distance G is suitably in theorder of 70-120 mm. As mentioned above, the essentially plane area ofthe crotch of women directly in front of the genitals has a length of inthe order of 80-100 mm, that is to say all women are essentially thesame size in this plane area. It has been found that a crotch dimensionG on the product of in the order of 70-120 mm functions well for mostwearers. The larger the angles a and γ and the stiffer the stiffeningelement, the more important it is that the crotch dimension on theproduct corresponds to the length of the plane crotch portion of theintended wearer directly in front of her genitals if the product is notto feel uncomfortable.

It may therefore be suitable to have a range of sizes of the productaccording to the invention depending on the selection of stiffness andsaid angles, so that different wearers can find a suitable size withregard to dimensions and angles. This of course applies to all theembodiments of the invention described here but is particularlyimportant when the product is intended to be anchored both at the frontand at the rear. The requirement for size adaptation also increases forall the embodiments the stiffer the absorbent element is.

The stiffening element and at the same time the absorption element 6 inthe embodiment according to FIG. 5 has a cutout 13. As in the otherillustrative embodiments described above, this is wedge-shaped but has alarger angle β which in FIG. 5 is obtuse. The angle β can be variedwithin wide limits between 10° and 120°. How large a cutout 13 isrequired depends on the function required of the legs 14 and 15 and onthe absorption capacity desired in the rear portion 2 of the product.

The smaller the angle β with the same width on the rear portion as awhole and with the same angle γ, the wider the legs 14, 15 are, which inturn results in increased absorption capacity and increased stiffness inthe rear portion.

The size of the cutout also affects the height of the fold 17. Thisheight of the fold and the shaping of the rear piece 2 also depend onthe pretensioning and extent of the elastic means 16.

The illustrative embodiment of the product according to the inventionshown in FIG. 5 can serve as, for example, a night towel. Like the otherembodiments, this embodiment is also suitable as an incontinence pad.This type of protection is to be capable of dealing with rapidlyreceiving large quantities of liquid discharged at a great flow ratefrom the wearer.

A product of the type shown in FIG. 5 can, in combination withsupporting briefs or with elastic pants adapted specially for supportingthe product, serve as a nappy for receiving both urine and faeces. Ifthe product is to serve as a nappy, the cutout 13 should be relativelylarge, corresponding on the whole to the embodiment shown in FIG. 5, inorder that it will be possible for discharged faeces to be taken up inthe cutout 13 of the rear portion.

FIGS. 6-8 show a suitable embodiment of a product according to theinvention. This embodiment corresponds in many respects to theembodiments according to FIGS. 1-4, and those parts corresponding to thesame parts in the embodiments described above have been provided withthe same reference numbers in the drawing.

A way of reducing further the risk of edge leakage caused by thesanitary towel being deformed during use, in addition to the arrangementof the stiffening element 6, is to provide the sanitary towel with araised portion, what is known as a hump, which is intended to makecontact with the genitals of the wearer during use of the sanitarytowel. Discharged bodily fluid can in this way be caught as soon as itleaves the body of the wearer and be absorbed immediately into theproduct instead of running out over the surface of the latter.

In the embodiment shown in FIGS. 6-8, the hump is brought about by ahump-forming element 24 which, as can be seen most clearly from FIG. 8,is arranged below the stiffening element 6 inside the liquid-impermeableouter layer 5. The positioning of the hump-forming element results in anumber of advantages. Admission of bodily fluid is not interfered withby hump material in direct proximity to the genitals of the wearer, butthe parts located closest to the genitals of the wearer can be optimizedwith regard to admission and absorption capacity. The positioningselected for the hump-forming element below the stiffening element 6 incombination with the positioning along the crotch portion of the productalso results in the positive effect that the product curves and shapesitself in the desired manner when fitted on the wearer. At thetransition 12 between the crotch portion 3 and the front portion, apoint of inflexion is formed, in front of which, that is to say in thefront portion of the product, the product is concave at least over aportion closest to said transition 12. Behind said point of inflexion,that is to say along the crotch portion of the product, the product is,in the area directly in front of the hump-forming element, convex, thatis to say the stiffening element 6 is curved in this area, upwards inthe crotch portion 3, as can be seen most clearly from FIG. 8. Inaddition to bringing about the raised portion on the front side of theproduct, the hump-forming element makes it possible to guide thestiffening element in the desired direction of curvature at differentpoints of the extent of the stiffening element.

The hump-forming element 24 consists of, for example, a non-absorbentsynthetic wadding which has resilient properties. Such a hump-formingelement retains its shape and function even when the material is in awet state.

The hump-forming element can also consist of a foamed material, forexample polyurethane foam.

As the hump-forming material is, in the embodiment shown, located belowthe absorbent element, which also serves as the stiffening element, thehump-forming material can be liquid-absorbing. In such an embodiment, itis suitable to select a material which has larger capillaries than theabsorption element has, so that liquid can be transported to thehump-forming material only when the absorption element is saturated withliquid. A hump-forming absorbent fibrous layer which has resilientproperties only in the dry state can therefore also be used in such aconstruction because the material is essentially dry until theabsorption element itself is saturated with liquid. The positioning ofthe hump-forming element 24 below both the stiffening and the absorbentelement therefore affords a number of important advantages.

The element forming the raised portion has an elongate shape and extendsover the entire crotch portion in the illustrative embodiment shown. Thelength of the raised portion can vary between roughly 20 mm and 120 mm.

The element 24 forming the raised portion is narrower than the productas a whole in the crotch area. In this way, it is possible for laterallysurrounding portions 25, 26 of the product as a whole to shapethemselves around the element 24 forming the raised portion. Thematerial forming the raised portion is suitably at least twice as thickas the surrounding areas 25, 26.

In FIG. 8, the product has been shown in curved, three-dimensional formfor the sake of clarity. An absorbent product of the type described hereis of course always three-dimensional in the conventional sense, that isto say it has length, width and thickness.

In this context, however, the term three-dimensional means that theproduct must be curved in some way to adapt to the body shape of thewearer.

In this context, the term plane form means that the product isessentially plane. The product shown in FIGS. 6 and 7 is essentiallyplaniform according to this definition in spite of the fact that theelastic means draws the material layers together in the cutout 13between the legs 14, 15.

Products in plane form according to FIGS. 6 and 7 can be packed simply,for example in stacks in a box or bag and yet, when put on, be made toadopt an anatomically adapted three-dimensional shape, as shown in FIG.8, without any measures whatsoever.

By virtue of its special construction with the dimension of the distanceM between said muscle tendons, the hump-shaped element 24, the action ofthe elastic means 16 and the stiffness and geometric shape of thestiffening element 6, the product is anatomically adapted andpredestined to adopt during handling a three-dimensional shape accordingto FIG. 8 adapted to the body shape of the wearer.

In the illustrative embodiment shown, the stiffening and at the sametime absorbent element 6 has the same stiffness properties over itsentire extent. As a result, uncontrolled creases, which could give riseto uncontrolled and unintentional liquid flow, do not normally ariseover the extent of the stiffening element. At the transition 12 betweenthe crotch portion 3 and the front portion 1, a curvature is initiatedbecause the product as a whole changes its flexural resistance here, onthe one hand on account of the hump-forming element having its enddirectly in front of this transition and on the other hand because thestiffening element is at its narrowest here with a dimension M adaptedto the distance between said muscle tendons on the wearer. At thistransition 12, a point of inflexion 27, or rather a line of inflexion,is formed, in front of which the product is concave and bowl-shaped,whereas it adopts a convex shape behind this point of inflexion 27. Ascan be seen from FIG. 9, it is suitable for the hump-forming element tobe rounded at the front along a line 28. In this way, the stiffeningelement is caused by this rounded line to adopt an evenly rounded bowlshape in the front portion, as can be seen from FIG. 9.

In the transition area 20 between the crotch portion 3 and the rearportion as well, it is suitable for the hump-forming element 24, whichin the embodiment shown extends as far as said transition area 20, to berounded at its rear end. As a result, no undesirable creases arise, butthe transition between the convex crotch portion and the two sideportions of the rear portion 2 sloping downwards around the fold 17formed by the elastic means 16 is even and smooth without undesirablecreases.

The raised portion formed by the hump-forming element 24 also has theadvantage that the fold extending into the cleft between the buttocks ofthe wearer does not extend in too abruptly or too far and give rise tochafing. In this respect also, the hump provides a soft transition inthe transition area between the crotch portion and the rear portion.

In all the embodiments described above, it is suitable for the productto be provided with a pressure-sensitive adhesive on the outside of itsliquid-impermeable outer layer 5. This has been indicated in FIG. 7 byadhesive strands 29 which, before use of the product, are covered in aconventional manner by a cover strip (not shown) treated with releaseagent. Although the product according to the invention is anatomicallyadapted, it is suitable, for reliable secure positioning, to have apressure-sensitive adhesive on the liquid-impermeable outside of theproduct for interaction with the briefs of the wearer, which contributesto keeping the product in the intended position on the wearer.

FIG. 10 shows an embodiment in the form of a nappy. This has a frontportion 40, a crotch portion 41 and a rear portion 42. Outwardly, theembodiment shown of a product in the form of a nappy according to thepresent invention is designed in a conventional manner. The frontportion 40 and the rear portion 42 are intended to be arranged aroundthe waist of the wearer when the nappy is put on and to be closed in thefitted position by means of tape flaps 43, 44. In FIG. 10, the nappy isshown diagrammatically in plane form from the inside and is providedwith a covering in the form of a liquid-permeable inner layer 45,suitably made of what is known as a non-woven, and an outer layer madeof thin plastic film (not shown), suitably made of polyethylene. Insidethe inner layer, an essentially hourglass-shaped absorption layer 46 isindicated, which is thin and very flexible. Leg elastic 47, 48, which isintended to close tightly around the thighs of the wearer during use ofthe nappy, has been arranged along the edge portion in the crotchportion.

FIG. 10 shows diagrammatically a stiffening and at the same timeabsorbent element 6 of the same type as in the illustrative embodimentsdescribed above. The components corresponding to similar parts in theillustrative embodiments described above have been provided with thesame reference numbers in FIG. 10. The stiffening absorbent element isanatomically adapted in the same manner as in the illustrativeembodiments described above, with a dimension M adapted to the distancebetween said muscle tendons directly in front of the groins and with acrotch length G adapted to the crotch length of the wearer and withangles and geometry also as described above.

A nappy according to the invention of the type shown in FIG. 10 has asuperior fit compared with conventional nappies. The presence of thestiffening element means that, when the nappy is put on, it is guidedinto the correct position on the wearer and that it remains in thisposition during use of the product.

In all the illustrative embodiments described above, the width of thestiffening and at the same time absorbent element 6 increasescontinuously from the transition 12 between the front portion 1 and thecrotch portion 3 to the transition area 20 between the crotch portion 3and the rear portion. One reason for this is that the available spacebetween the legs of the wearer is very limited and it is important toutilize the width of this area optimally. The width can increase in theorder of 1.5 times between the transition 12 and the transition area 20without the wearer finding it uncomfortable. Another reason is that theproduct is more stable on the wearer when the stiffening element is madeas wide as possible along the crotch portion.

The invention is not limited to the illustrative embodiments describedabove, but a large number of modifications are possible within the scopeof the patent claims below.

For example, anatomically shaped stiffening and absorbent elements ofthe type described above can be arranged in what are known as nappypants, that is to say where the nappy is integrated into disposablepants.

It has been stated above that the stiffening absorbent element can bemade from different materials and from laminates or one or morematerial(s). The stiffening absorbent element can also be made from morethan one layer and with the extent of the individual layers beingdifferent, in which way it is possible for different areas of thestiffening element to have different stiffness.

As mentioned above, the stiffening element can consist of all thematerial layers and bonding agents included. Different stiffness indifferent areas of the stiffening element can therefore also be obtainedby varying the degree of connection in different areas, for exampledifferent quantities of adhesive in different areas and even the absenceof adhesive or other bonding agent in different areas between or inindividual layers.

The weight per unit area of the stiffening element produced from adry-formed fibre mat is not limited to the order of 100-400 g/m², butother weights per unit area are possible within the scope of theinvention.

The elastic means 16, which is arranged in the cutout 13, has beenindicated in the illustrative embodiments described above as having beenarranged in a pretensioned state. However, in the manufacture ofabsorbent products such as sanitary towels, nappies and the like, it isknown to arrange a heat-sensitive elastic means in an untensioned stateand tension the elastic by heat treatment. This usually takes place whenthe articles are packed.

1. An absorbent product comprising: a longitudinal direction and atransverse direction; a front portion; a rear portion; a crotch portionlocated between the rear portion and the front portion; an absorbentelement; a liquid-tight layer; and a stiffening element intended tocontribute to the three-dimensional shape of the product during its use,wherein the stiffening element is in a plane state before use of theproduct, the stiffening element extends in the longitudinal direction ofthe product over the crotch portion and at least some way in over thefront portion, the stiffening element has a stiffness in the dry stateof in the order of 1-15 N measured according to ASTM D 4032-82, thestiffening element has a width M at a transition between the crotchportion and the front portion which is adapted to the distance betweenthe muscle tendons of the wearer on both sides of the crotch of thewearer in the groin of the latter and which is of the order of 15-45 mm,and wherein the product has different stiffness along a centre lineextending in the longitudinal direction thereof, as a result of whichthe product is predestined to curve in predetermined places along saidcentre line when the product is fitted on the wearer, and the stiffeningelement comprises a dry-formed fibre mat with a density between 0.15 and0.75 p/cm3 and a weight per unit area of in the order of 100-400 a/m2.2. The product according to claim 1, wherein side edges of thestiffening element in the front portion of the product diverge in thedirection from the crotch portion at least some way in over the frontportion, and wherein the side edges of the stiffening element, in thedirection from the crotch portion, form an acute angle α with a line inthe longitudinal direction of the product.
 3. The product according toclaim 1, wherein the stiffening element is absorbent and at the sametime constitutes the absorbent element, and wherein it swells duringabsorption while on the whole retaining its geometry in the transversedirection of the product.
 4. The product according to claim 1, whereinthe width M of the stiffening element at the transition between thecrotch portion and the front portion is of the order of 20-35 mm.
 5. Theproduct according to claim 1, wherein the width M of the stiffeningelement at the transition between the crotch portion and the frontportion is of the order of 25-30 mm.
 6. The product according to claim1, wherein the dry-formed fibre mat is, after compression, mechanicallysoftened to a desired stiffness.
 7. The product according to claim 1,wherein the dry-formed fibre mat is imparted a desired reduced stiffnessand a desired extensibility by virtue of a degree of compressionselected and a compression pattern selected.
 8. The product according toclaim 1, wherein the stiffening element has different stiffnesses indifferent areas.
 9. The product according to claim 1, wherein side edgesof the stiffening element diverge at least some way from the crotchportion in over the front portion of the product, and are arranged so asto form an angle between a line in the longitudinal direction of theproduct and each of said side edges of in the order of 35-55° C.
 10. Theproduct according to claim 9, wherein the angle is in the order of 45°C.
 11. The product according to claim 1, wherein the stiffening elementalso extends some way in over the rear portion of the product, andwherein, in the rear portion, side edges of the stiffening element, inthe direction from the crotch portion, diverge at least some way fromthe crotch portion in over the rear portion of the product.
 12. Theproduct according to claim 1, wherein the stiffening element alsoextends some way in over the rear portion of the product and has acutout in the rear portion extending from the end edge of the stiffeningelement in a direction of the crotch portion, as a result of which theproduct is during use imparted a fold along the longitudinal directionof the product in said cutout, which fold extends into the cleft betweenthe buttocks of the wearer during use of the product.
 13. The productaccording to claim 12, wherein said cutout is wedge-shaped andsymmetrically located and forms an angle β of between 10° C. and 120° C.at an end of the cutout facing the crotch portion.
 14. The productaccording to claim 13, wherein the angle is 15° C. to 40° C.
 15. Theproduct according to claim 1, wherein the stiffening element alsoconstitutes the absorbent element, wherein the stiffening element has astiffness of at least 1.0 N measured according to ASTM D 4032-82, andwherein the stiffening element is designed with essentially the samestiffness over an entire extent of the stiffening element.
 16. Theproduct according to claim 1, wherein a hump-forming element comprisinga resilient material is arranged under the absorbent element over atleast a part of the crotch portion, the hump-forming element beingarranged so as to bring about a raised portion on a side which isintended to be fitted against a wearer, the raised portion beingarranged so as to come to lie directly in front of genitals of thewearer after fitting of the product on the wearer.
 17. The productaccording to claim 16, wherein the raised portion is elongate in thelongitudinal direction of the product and has a length of between 20 mmand 120 mm.
 18. The product according to claim 16, wherein the raisedportion is narrower than the product as a whole in the crotch area, andwherein the raised portion is at least twice as thick as surroundingareas.
 19. The product according to claim 1, comprising: an elasticmeans arranged in the longitudinal direction of the product andcentrally along the rear portion of the product and at least along apart thereof from the crotch portion, which elastic means is intended,along its length, to draw adjacent material portions together and curvethe product upwards for better contact with the body of the wearer. 20.The product according to claim 1, wherein the stiffening element servesas an absorption means and has very great liquid-spreading capacity forspreading bodily fluid received in a relatively narrow crotch areabounded by the anatomy of the wearer directly in front of genitals ofthe wearer over the absorbent portions of the whole product, and whereinthe stiffening element is designed with a great swelling capacity in adepth direction and an attendant great absorption capacity.
 21. Theproduct according to claim 1, wherein the stiffening element also servesas an absorption element and is essentially homogeneous over its entireextent with regard to thickness, stiffness, spreading capacity andabsorption capacity, as a result of which the stiffening element andthus also the absorption element curve evenly during use and only inintended places without forming local irregularities which may give riseto undesirable spreading of liquid.
 22. The product according to claim1, wherein a length of said transition between the crotch portion andthe front portion, in which the width M of the stiffening element isadapted to the distance between the muscle tendons of the wearer on bothsides of the crotch of the wearer in the groin of the wearer, is in theorder of 5-15 mm.
 23. The product according to claim 22, wherein thestiffening element also constitutes the absorbent element, and in thatthe width of the stiffening element after said transition increasescontinuously in the crotch portion in a backward direction towards therear portion for the purpose of optimally utilizing available widthspace in this area with regard to maximum absorption.
 24. The productaccording to claim 1, wherein the product is arranged so as, by virtueof the stiffness selected for the stiffening element and by virtue of aselection of a geometry and dimensions in and around the transitionbetween the crotch portion and the front portion, when the product ispositioned in connection with it being put on with the transitionbetween the front portion and the crotch portion between said muscletendons, to be fixed in between these and in this way be transformedfrom a plane form to a three-dimensional form with the front portioncurved upwards in relation to the crotch portion and forming a bowl-likeshape at least in an area next to the crotch portion.
 25. An absorbentproduct comprising: a longitudinal direction and a transverse direction;a front portion; a rear portion; a crotch portion located between therear portion and the front portion; an absorbent element; a liquid-tightlayer; and a stiffening element intended to contribute to thethree-dimensional shape of the product during its use, wherein thestiffening element is in a plane state before use of the product, thestiffening element extends in the longitudinal direction of the productover the crotch portion and at least some way in over the front portion,the stiffening element has a stiffness in the dry state of in the orderof 1-15 N measured according to ASTM D 4032-82, the stiffening elementhas a width M at a transition between the crotch portion and the frontportion which is adapted to the distance between the muscle tendons ofthe wearer on both sides of the crotch of the wearer in the groin of thelatter and which is of the order of 15-45 mm, and wherein the producthas different stiffness along a centre line extending in thelongitudinal direction thereof, as a result of which the product ispredestined to curve in predetermined places along said centre line whenthe product is fitted on the wearer, and the crotch portion has a lengthof in the order of 70-120 mm.